If you go to Old Trafford in a derby, go down to 10 men in the first 25 minutes and still come away with a 1-0 victory, it tells you a lot about your players. Sunday's result was a statement win for Manchester City's new manager Enzo Maresca, who got his tactics spot on, but his team's performance will have showed him exactly what they are about.

I am talking about the mentality, discipline, organisation and energy you need in order to get a result when things go wrong for you like that in a game. They were smart too, and that experience and ability not to panic goes a long way in football in situations like the one City faced following Phil Foden's early red card.

City are used to always having most of the ball but they were fine without it against United. That is down to leadership and communication - not just from the manager, but from the players on the field. Maresca deserves plenty of credit for his decisions too, but he must be thinking he is a lucky man for having the group of players he does, because their intelligence and resilience was key.

As I said on Match of the Day, if anyone is doubting the competitiveness of City this season, just watch that game.

When it was 11 v 11, I thought United were the better team. They pinned City back and were really bright going forward. Marcus Rashford, especially, was really positive and it felt like Michael Carrick's side were in the ascendancy. The sending-off, which was the right decision by the way, kind of stopped United's momentum a little bit and also basically told City how they were going to have to play - they were going to have to defend for most of the game.

It is not what they are used to, but when you've got really experienced international players who are comfortable and calm, they don't really mind having to adapt. They actually seemed to enjoy the challenge, and straight away they were well-organised and very disciplined.

United did not really create too much in the second part of the first half, other than a Rashford free-kick that hit the post, but I was thinking they would make a few tweaks at half-time and come out and really go after City. That didn't happen though.

After Foden was sent off after 23 minutes, Maresca made only one change in the first 80 minutes of the game, when he replaced Cherki with Ndiaye at half-time. United hit the post again in the second half, with Kobbie Mainoo's shot from distance, but they did not really create a clear-cut chance until Gianluigi Donnarumma saved from Bryan Mbeumo right at the end of the game.

Other than that, their decision-making in the final third wasn't great. They were shooting from silly angles or, when they got in some good wide areas and put the ball in, there were not enough numbers in the box. United could also have changed their team around and brought on Benjamin Sesko earlier than they did, while I thought Rashford should have stayed on instead of Matheus Cunha because he was more of a threat.

But whatever United did try, City managed the game brilliantly. Even at the time, I thought their winning goal really shouldn't have stood, because Enzo Fernandez impacts play and should have been ruled offside, but their defensive display was outstanding, and not just from their back four and central midfielders.

Carrick made two substitutions during Sunday's derby, replacing Youri Tielemans with Sesko after 67 minutes and then bringing on Joshua Zirkzee for Rashford after 83 minutes. City were also superb further up the field. Antoine Semenyo and Erling Haaland were keeping the ball when it was played up to them, as well as winning free-kicks or beating people.

When he came on for Rayan Cherki, Iliman Ndiaye again did all of that brilliantly. He gave them a different dimension, and was a big reason they won the game. That substitution was a clever one by Maresca and brave too, because while Ndiaye is better than Cherki defensively, he is also a ball-carrier who travels with the ball better too.

I remember Maresca making a couple of negative substitutions this time last year when his Chelsea side went down to 10 men early on at Old Trafford. They ended up losing the game and he got a bit of criticism for it, but this time he went with Ndiaye, and it worked a treat. He gave them an outlet and made some great runs - he was part of everything they did positively from an attacking point of view and was even involved in the goal - but also did his share of defending, and winning the ball back.

As the game went on, it looked like United were the ones who looked tired despite having the extra man for so long. Maybe that was down to them playing on Thursday night, while City had their Champions League game on Tuesday, but it was not just energy that United were lacking. They simply did not have the know-how to cause City problems.

Let's not forget Donnarumma's late save because it was a brilliant stop, but Maresca's men were comfortable most of the time.

Danny Murphy was speaking to BBC Sport's Chris Bevan.

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